The present invention relates to an incubator which changes a temperature of a reaction sample such as a deoxyribonucleic acid (DNA) obtained from blood, a specimen or the like to accelerate a reaction of incubation (amplification) or the like.
As a conventional incubator of such a type, there is an automatic DNA or RNA synthesizer or the like based on a phosphotriestel method. This synthesizer is constructed by covering an outer periphery of a reaction vessel with a heat block, mounting a thermomodule which has a heating/cooling function based on Peltier effect on the heat block, and burying the thermomodule.
The synthesizing method of DNA or the like based on the phosphotriestel method repeats four steps of masking, deprotection, drying and condensation in this order to accelerate DNA proliferation. Thus, the synthesizer is adapted to carry out the three steps of masking, drying and condensation by putting a sample mixed with DNA and various reagents/solutions in the reaction vessel, and controlling energization of the thermomodule by a thermistor to heat the heat block to +42° C., and the step of deprotection by changing an energization direction of the thermomodule to cool the heat block to +20° C. (e.g., see Jpn. UM Appln. KOKOKU Publication No. 62-44979).
However, in the process of repeating the four steps, the solution evaporated from the reaction vessel during the heating causes dew condensation on an upper part in the reaction vessel during the cooling, consequently creating a problem of a reduction in a water level of the solution. Therefore, there has been a problem that the specimen such as DNA is exposed from the solution to disable a proper reaction of incubation (amplification).
Conventionally, the aforementioned problems have been solved by an incubator 100 similar to that shown in FIG. 18. That is, in the incubator 100, a reaction chamber 102 is formed on an upper surface of an incubator body 101, and a reaction block 103 is mounted in the reaction chamber 102 to execute heating or cooling by heating means or cooling means (not shown). A heat insulating cover 105 comprising an upper heating plate 104 on its lower surface is disposed above the reaction chamber 102 in which the reaction block 103 has been mounted. This heat insulating cover 105 is rotated upward to be opened by pivotally supporting its rear end rotatably on the incubator body 101. A reference numeral 106 in the drawing denotes an operation panel attached to a front of an attaching section 107 disposed by being inclined obliquely forward at a predetermined angle. The operation panel 106 comprises an operation section 108 and a display section 109.
Thus, in a reaction vessel (not shown) mounted on the reaction block 103, the heat insulating cover 105 is rotated downward to close the reaction chamber 102, thereby applying pressure to the reaction vessel from above, and an upper part of the reaction vessel is heated by the upper heating plate 104 disposed on the lower surface of the heat insulating cover 105. Accordingly, dew condensation on the upper part of the reaction vessel which occurs in the incubation (amplification) step of DNA or the like is prevented.
However, in the above constitution, the heat insulating cover 105 must be opened when the reaction vessel is attached/detached. In such a case, since the heat insulating cover 105 is rotated upward to be opened as described above, the upper heating plate 104 disposed on the lower surface of the heat insulating cover 105 faces a space for replacing the reaction vessel. Thus, there is a danger that a worker who replaces the reaction vessel easily touches the upper heating plate 104 to be burned.
Thus, the heat insulating cover 105 may conceivably be moved in a linear direction to be opened/closed while its lower surface is maintained down. However, there is a problem of a complex structure because a mechanism is necessary to press the reaction chamber 102 by the heat insulating cover 105.
Furthermore, in the above constitution, the operation panel 106 which comprises the display section 109 for displaying an amplification state in the reaction chamber and the operation section 108 for setting an amplification state is fixed at a specified angle by the attaching section 107. Thus, there is a problem that if the device is installed in a position other than a fixed height, visibility of the display section 109 and operability of the operation section 108 are bad.